The present invention relates to a sewing machine system including an electronically controlled sewing machine which is capable of performing an automatic sewing operation in accordance with a sewing data, and a programmer, which operates in association with the sewing machine, to prepare sewing data.
Heretofore, such an electronically controlled sewing machine has been known that a sewing operation is carried out automatically in accordance with a sewing data. In this type of sewing machine, a frame member movable along X and Y coordinates, which are defined on a plane perpendicular to a sewing needle, is placed below the sewing needle, a material (e.g., cloth) to be sewn being fixedly held to be moved together therewith. The frame member thus carrying the material to be sewn is moved by a drive motor for a certain amount defined in sewing data and a needle rod and a loop taker mechanism are driven to stitch. By repeating this process, the sewing operation is executed in accordance with the sewing data.
In the programmer of a conventional sewing system, stitch points are sequentially input using operation keys to create the sewing data which represents a series of stitch points. The sewing data is created, for example, by inputting a plurality of significant points, and the intermediate points having a predetermined pitch are interpolated between the significant points.
FIG. 7A is a chart schematically illustrating creation of the sewing data.
Firstly, a plurality of significant points S0, S1, S2, . . . , Sn along a pattern P to be sewn are input by an operator. The significant points are points on the pattern P and defining the shape or outline of the pattern. Then, intermediate points between successive two significant points are interpolated, by calculation, automatically. The intermediate points may be determined, for example, by a linear interpolation. Thus obtained points, (i.e. the significant points), the significant points and the intermediate points are points to be stitched, and are stored in a data recording medium such as a flexible disk or the like as sewing data.
It should be noted that the sewing data includes, in addition to the above-described stitch points data, supplemental data such as sewing speed data, thread cutting data and so on. For simplifying the description, such supplemental data will not be described in this specification.
When the sewing data is created, usually, the significant points are input, as numerical values, using operation keys provided on the programmer. In a conventional programmer, the input numerical values are displayed on a liquid crystal display or the like so that the operator can confirm the input values.
During preparation of the sewing data, however, progress is indicated only by the numerical values representing the stitch points. Although an experienced operator may do it, it is difficult to imagine the pattern or figure which would be formed when the input data is used for automatic sewing operation. In order to confirm that the intended pattern is formed, it is necessary to actually load the data in the electronically controlled sewing machine, and carry out the automatic sewing operation.